1. Field of the Invention
The present invention relates to a solenoid valve and more particularly to a solenoid valve for controlling an actuator by switching over the supply of pressure thereto, and furthermore the present invention more particularly relates to a means for fixing a main body including an electro-magnetic mechanism, a yoke member and a housing member comprised in the solenoid valve.
2. Statement of the Prior Art
A conventional solenoid valve of this kind is disclosed, for example, in Japanese patent application laid-open publication No. 55-139575 published on Oct. 31, 1980. This conventional solenoid valve includes a housing member 1, a plate member 2, a yoke member 3 and a main body 4 as shown by FIG. 5. The main body 4 including a part of an electro-magnetic (not shown) and a housing member 1 including the communication passages oppose to each other and contact with each other so that a valve means (not shown) for controlling the communication between the communication passages of the housing member 1 is provided therebetween. The plate member 2 is engaged with the housing member 1 and includes holes, and the yoke member 3 is engaged with the main body 4 at its one end portion and includes nail portions 3a fitted into the holes of the plate member 2 at its another end portion. And the yoke member 3 is secured to the plate member 2 by bending the nail portions 3a of the yoke member 3, and the housing member 1 and the main body 4 are airtightly pressed onto each other and are fixed to each other by securing the nail portions 3a of the yoke member 3 to the holes of the plate member 2.
In the above prior art of the solenoid valve, however, the yoke member 3 and the main body 4 are not fixed to each other directly and are only contacted with each other by the magnetic force. Accordingly, in this structure, if the solenoid valve receives repeated high acceleration external vibrations, the securing portions of the nail portions 3a of the yoke member 3 come loose. As a result, the electro-magnetic mechanism located in the main body 4 and the valve means are bent and are broken by the above vibration and the airtightness of the communication passages is lowered.